Adjustable-combustion-chamber furnace.



C. J. JOHNSON.

ADJUSTABLE GOMBUSTION CHAMBER FURNAGE.

APPLICATION FILED MAB.30,1914.

Patented Jan. 26, 1915.

H1 Z Y IUI UNITED STATES PATENT OFFICE.

CHARLES J'. JOHNSON, OF CEDAR RAPIDS, IOWA, ASSIGNOR T0 JOHNSON GAS APPLIANCE COMPANY, 0F CEDAR RAPIDS, IOWA, A CORPORATION.

ADJ' USTABLE-COMBUSTION-CHAMBER FURNACE.

Specification of Letters Patent.

Patented Jan. 26, 1915.

Application filed March 30, 1914. Serial No. 828,251.

To all whom it may concern:

Be it known that I, CHARLES J. JOHNSON, of Cedar Rapids, county of Linn, State of Iowa, manufacturer, have invented certain new and useful ImprovementsinAdjustable- Combustion Chamber Furnaces, of which the following is a full, clear, and exact de` scription.

This invention relates to furnaces in which a gaseous fuel burner is located ex ternal to an adjustable combustion chamber, and consists in means for regulating the cubical area or flame capacity of the adjustable chamber and for manipulating the furnace with greater facility than heretofore.

The object of my invention is to provide a combustion chamber adjustable as to size, regardless of the dimensions of the object being heated, so that the surrounding space is of the right proportion to accommodate the flame being applied. It prevents distributing the flame on the one hand through too large a space, and on the other, smothering it within too limited an area.

Where the combustion chamber is of a xed size, and objects of different dimensions are heated, there is danger of too large a space being used for the distribution of the flame, or too small for the supplying of the amount of oxygen necessary for perfect combustion. .In either case the maximum efliciency is not obtained. A given quantity of gas or other fuel liberates a given number of heat units, and if they are distributed through too large a space, less than the maximum efliciency is obtained. If through too small a space, there is an insufficient supply of oxygen. In my invention the flame space within the combustion chamber is readily and quickly regulated at will, and by the same means provision is made for closing and opening the chamber with facility. I accomplish this result by means of the device shown in the accompanying drawings, forming a part of this specification, in which- Figure l shows a top view of the furnace and lamp, and Fig. 2 shows side View thereof, the furnace being partly broken away to show the interior thereof.

1 is the stand on which the furnace rests, 2 is the outer wall of said furnace, 3 is the lining thereof, preferably of fire brick, 4 is an interior or secondary bottom, furnished with projections 5 on which the object X rests. I have shown an ordinary pinion for X, which it is desired to raise to an intense heat, but these objects vary in form and size, and it is the accommodation of the furnace to these varying objects which is the essence of my invention.

6 is a lug on the side of the furnace 2 pierced with a hole to receive the pivotal lower end of a laterally swinging movable support 7 whose outer and upper end 8 is bifurcated to receive a vertically tilting arm 9, and 10 is a set screw to secure said arm 9 in any desired fixed position as to its vertical angle or tilt.

l1 is a chain or other central connection between the end of said arm and the top 12 of the combustion chamber. Said top 12, which determines the cubical area of the liame space within the furnace body, and is movable vertically to adjust the combustion chamber, is constructed with peripheral escape notches which locate escaping flames and products of combustion at a sufficient distance away from the central connection 11. It also is lined with fire brick 13.

1li is a counter balancing weight at the other end of said arm 9.

15 is a standard furnished with an upright 16 which carries an ordinary Bunsen burner 17, which is inserted in the furnace at 18.

19 is a gas hose conveying the fuel to the burner.

In Fig. 1 the dotted lines show the top 12 removed from over the furnace chamber, and carried to one side. In Fig. 2 the dotted lines show the said top lowered into the furnace, to diminish the size of the chamber, to accommodate a smaller object.

The device is operated by means of rais ing or lowering as desired the top 12, so that the space about the object to be heated is in proper proportion to the flame, and then fixing said top by means of the set screw 1'0. Vhen the space surrounding the object is the proper size to allow the flame to completely envelop said object and yet burn without smothering, the maximum efliciency is secured. A given quantity of gas or other heating element liberates a given number of heat units, which, if diffused in a chamber too large, a proportionately smaller number of said units come in contact with the object to be heated. If diffused in a chamber too small, combustion is incomplete by reason of a lack of the introduction of a proper 'amount vof oxygen. Y

What I claim asnew and desire to. secure 5 by Letters Patent of the United States is, The combination With la gaseous fuel burner of an open-topped furnace body having a flamespace in communication with said burner, a movable furnace top having 10 peripheral escape notches, and means for v adjustingv said top within said. Fbody or swinging said top clear of said body in- @hiding a super-jacent. eunterbalaned lever arm and connection at; the Center 0f Said peripherally notched top, substantially as 15 'Cpiothiyaientma11e-Obtained 'fr ve. cents each, by addressing the Cmmission/er ef Patents.:

` Washington, D. Q. 

